From mboxrd@z Thu Jan  1 00:00:00 1970
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Subject: Re: [PATCH 07/31] lmb: Add reserve_lmb/free_lmb
Date: Tue, 30 Mar 2010 10:31:31 +1100
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To: michael@ellerman.id.au
Cc: Yinghai Lu <yinghai@kernel.org>, Ingo Molnar <mingo@elte.hu>, Thomas Gleixner <tglx@linutronix.de>, "H. Peter Anvin" <hpa@zytor.com>, Andrew Morton <akpm@linux-foundation.org>, David Miller <davem@davemloft.net>, Linus Torvalds <torvalds@linux-foundation.org>, Johannes Weiner <hannes@cmpxchg.org>, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org

On Tue, 2010-03-30 at 09:20 +1100, Michael Ellerman wrote:
> 
> But that's my point. You shouldn't need to touch the existing API, and
> you shouldn't need to add a new parallel API. You should just be able to
> add the logic for doubling the array in the lmb core, and then everyone
> gets dynamically expandable lmb. I don't see any reason why we want to
> have two APIs.

Ack.

> > > It seems to me that rather than adding these "special" routines that
> > > check for enough space on the way in, instead you should be checking in
> > > lmb_add_region() - which is where AFAICS all allocs/frees/reserves
> > > eventually end up if they need to insert a new region.
> > 
> > later i prefer to replace lmb_alloc with find_lmb_area + reserve_lmb.
> 
> Why? The existing code has been working for years and is well tested? 

I still don't totally understand why he needs a find_lmb_area()
anyways. 

It might be justified ... or not. I just want it to be better
documented.

Cheers,
Ben.